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Key points on temperature change of the past 2.00 years in China

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Progress in Natural Science:Materials International 2004年第8期 82-89页

作者： GE Quansheng 1, ZHENG Jingyun 1*, MAN Zhimin 2. FANG Xiuqi 3.1 and ZHANG Piyuan 1(1. institute of geographic {2. and Natural resources research, Chinese Academy of {2., beijing 100101, China 2. institute of Chinese History Geography, Fudan University, Shanghai 2.043., China 3. School of Geography, beijing Normal University, beijing 100875, China) institute of geographic {2. and Natural {3. research，Chinese Academy of {2.，beijing 100101，China institute of Chinese History Geography，Fudan University，Shanghai 2.043.，China School of Geography，beijing Normal University，beijing 100875，China institute of geographic {2. and Natural {3. research，Chinese Academy of {2.，beijing 100101，China

Temperature change of the past 2.00 years in China is discussed based on the winter half-year temperature series of the past 2.00 years in eastern China reconstructed recently, and other related studies. The main conclusions are as follows: (1) The Little Ice Age (LIA) in China began in the early of the 14th century (13.0}s) and ended in the beginning of the 2.th century (1910s), which was composed of four evident cold stages and three short warming stages. The cold period in the Wei, Jin and South-North dynasties (2.0s～560s) was the only one comparable with LIA for the past 2.00 years. (2. The Medieval Warm Period (MWP) in China began in the 93.s and ended in the 13.0s, which was composed of two warm stages over 100 years and a cold stage less than 100 years. (3. The climate in the Sui and Tang dynasties should be divided into two stages: the climate in the 570s～770s was as warm as that in the 2.th century; while the temperature in the 780s～92.s was lower than that in the 1950s～1970s. (4) In eastern China as a whole, winter half-year temperature variation with over 1 ℃ occurred between the cold and warm stages on centennial scale, while the changing rate exceeded 1.0 ℃ per century. (5) There exists an about 13.0-year periodicity in the historical temperature change. Inferred from the periodicity, the most likely historical analogue for the warming in the 2.th century is the warm stage of the Sui and Tang dynasties (570s～770s), instead of the Medieval Warm Period. (6) Although it was critically warm, the temperature of the 2.th century in eastern China is still within the threshold of the variability of the last 2.00 years.

关键词： eastern China past 2.00 years temperature change.

A general model for estimating actual evaporation from non-saturated surfaces

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Journal of geographical sciences 2002年第4期12卷 479-484页

作者： QIU Xinfa1,2. ZENG Yan3. LIU Changming3.1. Dept. of Urban && Resource Science, Nanjing University, Nanjing 2.0093. China 2. Dept. of Geography, Nanjing {3. of Meteorology, Nanjing 2.0044, China 3. Inst. of geographic {2. and Natural resources Dept. of Urban & Resource Science Nanjing University Nanjing China Dept. of Geography Nanjing Institute of Meteorology Nanjing China Inst. of geographic sciences and Natural {2. {3. CAS Beijing China

Based on energy balance equation and mass transfer equation, a general model to estimate actual evaporation from non-saturated surfaces was derived. Making use of two concepts, “relative evaporation” and “relative drying power”, a relationship was established to account for the departure from saturated conditions. Using this model, the actual evaporation (evapotranspiration) can be calculated without the need of potential evaporation estimation. Furthermore, the model requires only a few meteorological parameters that are readily and routinely obtainable at standard weather stations. Based on nearly 3. years data of 43.0}meteorological stations and 512.hydrological stations in China, in combined with GIS, nine typical river basins were selected. Using the data of the selected river basins, the model was tested. The results show that the actual evaporation rate can be estimated with an error of less than 10% in most areas of China, except few years in the Yellow River Basin.

关键词： potential evaporation actual evaporation

Reconstructing temperature change in Central East China during 601-92. AD

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Science Bulletin 2010年第34期 3946-3956页

作者： GE QuanSheng,LIU HaoLong,ZHENG JingYun & ZHANG XueZhen institute of geographic {2. and Natural {3. research,Chinese Academy of {2.,beijing 100101,China

Using historical records on first and last frost and snow,spring cultivation,David peach blossom,autumn crop harvest,grade of sea freeze and change in northern citrus boundary,we reconstructed temperature change during 601-92. *** mean temperature of the winter half-year(October to April)over Central East China during this period was about-0.2.°C higher than that of the present(1961-2.00 AD mean).During 601-82. AD,mean temperature was about-0.52.C higher than the *** 82.-92. AD,the mean temperature was 0.42.C lower than the *** temperature fluctuations were characterized by a maximum amplitude of 1.05°C at the centennial scale,1.3.°C at the 50-year scale,2.02.C at the 3.-year scale,and 2.3.C at the 2.-year *** were four peaks warmer than today(601-62. AD,mean of 1°C higher temperature;641-660 AD,1.44°C;701-72. AD,0.88°C;781-800 AD,0.65°C).Three cold periods were in 741-760,82.-840,and 881-900 AD,the mean temperature of which was 0.3.-0.87°C lower than the present.

关键词： Sui and Tang Dynasties Central East China phenological record human impression record reconstruction of tempera-ture change

De-farming and Ecological Restoration in the Loess Hilly-gully Region in Northern China

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Journal of Mountain Science 2006年第2期3卷 168-177页

作者： XU Yong TANG Qing MA Dingguo GUO Tengyun institute of geographic {2. and Natural {3. research CAS Beijing 100101 China

De-farming has been a powerful measure taken by the central and local governments of China for ecological restoration in the loess hilly-gully region since 2.00. In years past, aid-based de-farming pattern was far and wide popularized in the region and terrace-based de-farming pattern demonstrated in a few small watersheds was also rather effective for ecological restoration. After summing up the features of three patterns (aid-based de-farming slope farmland more than 2.°(AD2.), aid-based de-farming slope farmland more than 15° (AD15) and terrace-based de-farming (TD)), this paper analyzed the regional difference of these patterns in de-farming area, ecological restoration, investment demand and so on. The results show that there are two crucial areas in the loess hilly-gully region for ecological restoration at the moment, the policies adaptation to the different areas should be constituted as soon as possible and the limited fund should be devoted to the two crucial areas.

关键词： De-farming ecological restoration loess hilly-gully region China

Spatial-Temporal Changes of Soil Organic Carbon During Vegetation Recovery at Ziwuling, China

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Pedosphere 2005年第5期15卷 601-610页

作者： LI Yu-Yuan SHAO Ming-An ZHENG Ji-Yong ZHANG Xing-Chang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 （China）

To probe the processes and mechanisms of soil organic carbon (SOC) changes during forest recovery, a 150-yearchronosequence study on SOC was conducted for various vegetation succession stages at the Ziwuling area, in the centralpart of the Loess Plateau, China. Results showed that during the 150 years of local vegetation rehabilitation SOC increasedsignificantly (P 3.respectively. The decrease in SOC from 60 to 150 years of abandonment implied that the soil carbon pool was a sink forCO2.before the shrubland stage and became a source in the later period. This change resulted from the spatially variedcomposition and structure of the vegetation. Vegetation recovery had a maximum effect on the surface (0-2. cm) SOCpool. It. was concluded that vegetation recovery on the Loess Plateau could result in significantly increased sequestrationof atmospheric CO2.in soil and vegetation, which was ecologically important for mitigating the increase of atmosphericconcentration of CO2.and for ameliorating the local eco-environment.

关键词： soil organic carbon density spatial-temporal change vegetation recovery vegetation succession

Spatial pattern and compositive structure of forests in Guizhou

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Journal of geographical sciences 2002年第4期12卷 413-419页

作者： YAO Yonghui1, ZHANG Baiping1, ZHOU Chenghu1, LUO Yang2. ZHU Jun2. QIN Gang2. LI Baolin1, CHEN Xiaodong1(1. Inst. of {3. sciences and Natural {2. research, cas, beijing 100101, China 2. Inst. of Forestry Survey and Design of Guizhou Pr Inst. of geographic sciences and Natural {2. {3. CAS Beijing China Inst. of Forestry Survey and Design of Guizhou Province Guiyang China

Remote-sensing and field data of Guizhou forest resources in 2.00 are processed using ArcGIS, with the production of forest resource distribution map, forest age class structure map, and forest canopy distribution map. Analysis of these data shows that: (1) though there are multiple types of forest resources, forest coverage is low (only 2..2.%, excluding sparse woodland, shrub and underage-forest); (2. the {2.al distribution of forests is quite uneven, mainly in the southeast of the province and in Zunyi prefecture; (3. the zonal evergreen broad-leaved forests have been seriously destroyed, with striking secondary features, i.e., coniferous forest and shrubbery account for the greatest proportion of Guizhou forests; (4) the timber-forest is much larger in area than shelter-forest and economic forest; (5) young-and-middle aged forests are more widely distributed than near-and-over matured forest; and (6) the forest of Guizhou is not enough to effectively protect the environment of karst mountain areas of the province.

关键词： forest resources spatial pattern compositive structure Guizhou

Automatic generalization of metro maps based on dynamic segmentation

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Science China(Technological sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2.& ZHANG Yi 2.1 institute of Geography and Remote Sensing,{3. Normal University,{3. 100875,China 2.institute of Remote Sensing and geographic Information System,Peking University,{3. 100871,China 1. institute of Geography and Remote Sensing Beijing Normal University Beijing 100875 China 2. institute of Remote Sensing and geographic Information System Peking University Beijing 100871 China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

Relationship Between Soil Properties and Different Fractions of Soil Hg

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Pedosphere 2001年第3期11卷 257-262页

作者： WU HONGTAO YU GUIFEN QING CHANGLE and CHEN TONGBIN Southwest Agricultural University, Chongqing 400716 (China) institute of geographic {2. and Natural {3., the Chinese Academy of {2., beijing 100101 (China) institute of Soil Science, th 西南农业大学重庆 400716 中科院南京土壤所江苏南京 210008 中科院地理科学与资源所北京 100101

Correlation and path analysis methods were used to study the relationship between soil properties and the distribution of different soil Hg fractions with nine representative soils from Chongqing, China. Results showed that clay (2.m) could increase water-soluble Hg (r = 0.700*). Soil organic matter (OM) could enhance the increase of elemental Hg (r = 0.674*). The higher the base saturation percentage (BSP), the more the residual Hg (T = 0.684*). Organic Hg, the sum of acid-soluble organic Hg and alkali-soluble Hg, was positively affected by silt (2.2. μm) but negatively affected by pH, with the direct path coefficients amounting to 1.0487 and 0.512., respectively. The positive effect of OM and negative effect of BSP on organic Hg were the most significant, with the direct path coefficients being 0.7614 and -0.852., respectively. The indirect effect of clay (2.μm) via BSP (path coefficient = 0.4186) was the highest, showing that the real influencing factor in the effect of clay (2.μm) on acid-soluble organic Hg was BSP. Since the available Hg fraction, water-soluble Hg, was positively affected by soil clay content, and the quite immobile and not bioavailable residual Hg by soil BSP, suitable reduction of clay content and increase of BSP would be of much help to reduce the Hg availability and Hg activity in Hg-contaminated soils.

关键词： different fractions soil Hg soil properties

Method for seasonal precipitation reconstruction derived from snow and rainfall archives in Qing Dynasty: A case study in Shijiazhuang

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Progress in Natural Science:Materials International 2004年第8期 90-96页

作者： ZHENG Jingyun*, HAO Zhixin and GE Quansheng(institute of geographic {2. and Natural {3. research, Chinese Academy of {2., beijing 100101, China) institute of geographic {2. and Natural {3. research Chinese Academy of Sciences Beijing 100101 China

Two methods to reconstruct seasonal precipitation are developed in terms of the soil surface water balance and field infiltration experiment by artificial rainfall. Seasonal and annual precipitation for the period of 173.～1910 are reconstructed from snow and rainfall archives in the Qing Dynasty through both methods. The seasonal precipitation series from 173. to 2.00 is also established. The results show that the time series of seasonal precipitation obtained from both methods are statistically significant and consistent, implying that the seasonal precipitation can be reconstructed accurately from snow and rainfall archives in the Qing Dynasty by the above two methods, and thus the Chinese precipitation data in a large area would be extended to the early 18th century from 2.th century (instrumental observation period).

关键词： seasonal precipitation reconstruction snow and rainfall archives physical model field experiment reliability.